This amended application (RO I MH/DA6096 1-01 A2) requests support for four and a half years (July 200 Ito December2005) to conduct a follow-up of Vietnam veterans whose risk levels for current suicidal behaviors have been projected from the results from the Washington University Vietnam Era Study - Phase III (VES-HI), carried out in 1996-97. The VES cohort originates from a study initiated by the White House in 1971 to address substance abuse and adjustment problems to civilian life among returning servicemen deployed to Vietnam. Two waves of in-person interviews were conducted by Washington University in 1972 and 1974 with two national probability samples of male Vietnam War veterans and a comparison sample of nonveterans (total target N=l,227). The 25-year follow-up (VES-Ill) implemented life crisis intervention protocols after a suicide occurred during fieldwork. Analyses of VES-Ill and two large general-population studies, the National Mortality Followback Survey, 1993, and the National Longitudinal Alcohol Epidemiologic Survey, 1992, together confirmed a significant excess risk of both suicide and suicide attempts among Vietnam veterans, within men of the age group of 40-60, controlling for demographic risk and protective factors. Alcoholism, drug use, depression, and trauma/PTSD appear to largely explain Vietnam veterans' excess risk. This application (VES-IV) will attend closely to protective factors mitigating suicidal risk to improve the precision of suicidal behavior prediction. Based on self-reports and a suicide behavior predictive scale, higher-risk (n=168) and lower-risk (n=250) target samples have been selected from VES-III to balance the considerations for scientific yields and challenges expected in the field. The scientific aims are to examine: 1) the mechanisms of coping and other protective factors using mixed qualitative and quantitative measures, including analyses of a) qualitative measures of appraisal, coping, religiosity, optimism, substance use, social networks, and barriers to care based on suicide episodes or negative events, b) quantitative measures of qualitative codes used in a), c) quantitative measures of episode/event-based and general coping, and d) quantitative measures of time-dependent protective factors; and 2) the interactions of risk and protective factors in predicting suicidal behaviors, using the measures including a) quantitative episode/event -based or time-dependent risk and protective factors obtained from VES-IV, and b) previous risk and protective factors obtained from VES-III and earlier waves. A human subject protection aim is added to: 3) provide follow-up treatment triage and access to an on-call suicide intervention for those with current suicidal risk. The study will provide a better understanding of the inner working of protective factors, and their interaction with risk factors, which were identified as a gap in knowledge in the literature. We hope the study's results will help guide intervention for those with known risks for suicidal behavior.